Relation between microstructure and some mechanical properties of dual-phase medium-C–Cr cast steel

The influence of dual-phase structure (ferrite + martensite) on the impact toughness and rate of abrasive wear for as-cast and normalized steel (0.29 C, 1.15 Mn, 0.9 Si and 0.95% Cr) is investigated. The increased grain refinement and the well arranged lamellar packets of martensite and ferrite obtained during intercritical quenching (from 810°C) of normalized and prequenched (from 880°C) steel created a satisfactory combination between toughness and abrasive wear resistance over those measured for intercritically quenched as-cast steel with or without prequenching.     

Evolution of virtual reality [Medicine]

Although original applications in virtual reality (VR) for medicine pertained to the planning of surgeries, efforts have now shifted to the use of data fusion, i.e. to fuse virtual patients onto real patients as a navigational aid in surgery. Eventually, medical care with multiple professionals will be provided in a shared virtual environment that incorporates shared decision making for an actual surgical intervention or a rehearsal. The major applications of virtual reality in surgery can be divided into three areas: virtual humans for training, the fusion of virtual humans with real humans for performing surgery, and virtual telemedicine shared decision environments for training of multiple players. The applications pertaining to the realisation of virtual reality in medicine can be categorised into two areas: generic models and patient specific models     

Towards video-based immersive environments

Video provides a comprehensive visual record of environment activity over time. Thus, video data is an attractive source of information for the creation of virtual worlds which require some real-world fidelity. This paper describes the use of multiple streams of video data for the creation of immersive virtual environments. We outline our multiple perspective interactive video (MPI-Video) architecture which provides the infrastructure for the processing and analysis of multiple streams of video data. Our MPI-Video system performs automated analysis of the raw video and constructs a model of the environment and object activity within this environment. This model provides a comprehensive representation of the world monitored by the cameras which, in turn, can be used in the construction of a virtual world. In addition, using the information produced and maintained by the MPI-Video system, our immersive video system generates virtual video sequences. These are sequences of the dynamic environment from an arbitrary view point generated using the real camera data. Such sequences allow a user to navigate through the environment and provide a sense of immersion in the scene. We discuss results from our MPI-Video prototype, outline algorithms for the construction of virtual views and provide examples of a variety of such immersive video sequences.     

The influence of size and healing content on the performance of extrinsic self-healing coatings

Among the several approaches for the protection of metallic structures from corrosion, covering with a polymeric coating has attracted more attention due to their convenient application, cost-effective price, and the relatively benign environmental impact. However, the polymeric coatings are sensitive to mechanical/thermal shocks and aggressive environments, leading to damages in the coatings that affect their barrier performance. Self-healing polymeric coatings have introduced remarkable development by extending the service life and reducing maintenance costs, leading to a significant boost in the reliability and durability of the conventional polymeric coatings. Among the different strategies to develop self-polymeric coatings, encapsulating healing agent within micro/nanocapsules, micro/nanofibers, and microvascular systems and incorporating them within the conventional coatings have been widely acknowledged as the most applicable approach. However, several factors, such as the effect of the healing system's size and content, have a significant influence on healing performance. Therefore, this review aims to reveal the effects of healing system size and healing content on the self-healing performance in polymeric coatings through the analysis of recently published articles.     

Thyroid Carcinoma: Phenotypic Features,Underlying Biology and Potential Relevance for Targeting Therapy

Thyroid carcinoma consists a group of phenotypically heterogeneous cancers. Recent advances in biological technologies have been advancing the delineation of genetic, epigenetic, and non-genetic factors that contribute to the heterogeneities of these cancers. In this review article, we discuss new findings that are greatly improving the understanding of thyroid cancer biology and facilitating the identification of novel targets for therapeutic intervention. We review the phenotypic features of different subtypes of thyroid cancers and their underlying biology. We discuss recent discoveries in thyroid cancer heterogeneities and the critical mechanisms contributing to the heterogeneity with emphases on genetic and epigenetic factors, cancer stemness traits, and tumor microenvironments. We also discuss the potential relevance of the intratumor heterogeneity in understanding therapeutic resistance and how new findings in tumor biology can facilitate designing novel targeting therapies for thyroid cancer.     

Generation of stable and narrow spacing dual-wavelength ytterbium-doped fiber laser using a photonic crystal fiber

Abstract

We demonstrate the design and operation of novel narrow spacing and stable dual-wavelength fiber laser (DWFL). A 70-cm ytterbium-doped fiber has been chosen as the gain medium in a ring cavity arrangement. Our design includes a short length photonic crystal fiber, acting as a dual-wavelength stabilizer based on its birefringence coefficient and nonlinear behavior and tunable band pass filter (TBPF) to achieve narrow spacing spectrum lasing. Our laser output is considered to be highly stable, with power fluctuation less than 0.8 dB over a period of 15 min. The flexibility and tunability of TBPF, together with polarization controller enable the spacing tuning of the DWFL from 0.03 nm up to 0.07 nm for 1040 nm region, and 0.10 nm up to 0.40 nm for 1060 nm region. The tunable wavelength spacing shows the flexibility of the DWFL in addition to stable and reliable properties of fiber laser in 1-μm region.     

Picomolar detection of insulin at renewable nickel powder-doped carbon composite electrode

A sol-gel technique was used for fabrication of a renewable carbon composite electrode (CCE) modified with nickel powder. This modified electrode shows excellent catalytic activity for the oxidation of insulin in alkaline solutions. The nickel powder was then oxidized to form a nickel oxide film electrode, which was used as an amperometric detector for hydrodynamic amperometry and flow injection analysis of insulin. It was found that the calibration curve was linear up to 30 microM with a detection limit of 40 pM under the optimized conditions for hydrodynamic amperometry using a rotating disk modified CCE. Flow injection amperometric determination of insulin at this modified electrode yielded a calibration curve with the following characteristics; linear dynamic range of 15-1000 pM, sensitivity of 8659.23 pA pM-1 cm-2, and detection limit of 2 pM. This electrode shows many advantages as an insulin sensor such as simple preparation method without using any specific electron-transfer mediator or specific reagent, high sensitivity, excellent catalytic activity, short response time, long-term stability, and remarkable antifouling property toward insulin and its oxidation product. Sensitivity, detection limit, and antifouling properties of this insulin sensor are better than all of the reports in the literature. Additionally, it is promising for monitoring insulin in chromatographic effluents.     

System of Multiple ANNs for Online Planning of Numerous Building Improvements

The aging infrastructure in North America and worldwide mandates large investments in repair and improvement (R&I) activities. For organizations that own many assets, managing a large number of R&I activities is not a simple task and requires accurate estimating and scheduling so that proper budgeting and resource allocation decisions can be made. To support these decisions, this paper introduces a Web-based system that estimates the cost and duration of a user-requested R&I activity and provides alternative schedules based on resource availability. For estimating, the Web-based system hosts 32 artificial neural networks (ANNs), trained on actual historical data, for 32 common R&I activities in building projects. Each ANN incorporates a sensitivity analysis to consider the uncertainty in the input parameters on the estimate, and is linked to a central scheduling algorithm for resource allocation based on a first-come first-serve basis. The automated system helps practitioners in planning numerous R&I requests with least time, cost, and paper work. Details on system development are provided in this paper along with perceived benefits and the opinion of users on its performance.     

A 10-bit 50-MS/s redundant SAR ADC with split capacitive-array DAC

A new architecture for successive-approximation register analog-to-digital converters (SAR ADC) using generalized non-binary search algorithm is proposed to reduce the complexity and power consumption of the digital circuitry. The proposed architecture is based on the split capacitive-array DAC with a simple switching logic as compared to the conventional non-binary SAR ADC architecture. A 10-bit 50-MS/s SAR ADC is designed based on the proposed architecture in a 0.18 μm CMOS technology. Simulation results show that at a supply voltage of 1.2 V, the SAR ADC achieves a peak signal-to-noise-and-distortion ratio of 59.5 dB, and a power consumption of 1.3 mW, resulting in a figure of merit of 33 fJ/conversion-step.